Apparatus to maintain spinal alignment during the squat exercise

ABSTRACT

The invention is an apparatus that allows weight resistance to be applied to the upper torso during the performance of the squat exercise and actively aligns the spine to reduce the chance of spinal injury. The apparatus consists of a set of pads or rests on the shoulders in front of the spine which are connected through a pivot or lever to a lower back rest or pad behind the spine which create and maintain spinal alignment. The pivot between the front and back rests, is positioned over, but not contacting, the spinal axis of the user and is the point at which resistance is applied.

CROSS REFERENCE TO RELATED APPLICATIONS

I hereby claim the benefit of my earlier provisional patent application “Lumbar Load Sharing Upright Squat Apparatus”, application No. 60/809,216.

BACKGROUND OF INVENTION

Throughout history man has manipulated heavy loads by placing poles, yokes, and bars across the shoulders and behind the neck. In this position the load would lie directly along a vertical-axis that traveled almost exclusively through supporting skeletal structures. While resting behind the neck, a straight line can be drawn from the load through the body going directly towards the ground. This line of application lies along the mechanical axis of the spine passes through the center of the pelvis, and exits at the point where the heels are placed on the ground. By having the load transmitted through skeletal structures, this line of application can support large amounts of weight with little risk of injury.

In industrialized societies, the use of shoulder-bone material handling has largely been eliminated. The primary remaining use of applying loads across the shoulders is in performing physical exercise. For the purposes of health, fitness, and athletic performance, individuals will apply loads across the shoulders and behind the neck while performing a deep knee bend maneuver. The added resistance of the shoulder-borne weight is beneficial in developing muscle in the lower extremities. As a general rule, an exercise movement in which the lifter is standing upright, bearing load across the shoulders and lowering and raising the torso by bending the knees and hips is called a “squat”.

The relative merits of this exercise have been debated for years, but it suffices to say that it is a widely performed exercise movement. One well recognized, significant concern with this movement has to do with amount of weight that is delivered to the spinal column during its performance. The spine is biomechanically designed to accommodate large axial loads while it is in the extended, upright posture. This is attributed to appropriately distributing the load across certain load bearing regions of each individual vertebra. In the area of most concern, the low back, these load bearing regions are called the anterior (front), middle, and posterior (rear) columns of the spine. The least capable area of bearing load is the anterior column of the lumbar spine. This is because the soft nucleus, or center, of the intervertebral disc is located here, and under excessive loading could potentially rupture. The middle column is more capable of load bearing. Here the load is resisted by the thick outer wall of the disc which can support large loads without risk of rupture. Finally, the posterior column is best suited to bear weight because it consists entirely of bony elements and joints which have high compressive strength capabilities.

The primary adaptation that the human body has made to protect the spine is to have the lumbar vertebra curve backwards to form an arch. The concave portion of the arch forms what is seen as the small of the back. This curved arch serves to compress down on the bony posterior column and the fibrous middle column, while unloading the softer nucleus in the front of the spine. This is the position that the spine must be held in during the squat exercise so that the load does not cause damage to the low back.

It can however be difficult to maintain an arch in the low back while performing squats. The most common error is among people first learning the movement. They can simply just lose their balance and lean forward. Also, even in experienced exercisers, fatigue of the back muscles, responsible for maintaining the back arch, can occur during the exercise and again the spine leans forward and the discs are endangered. Finally, the actual motion of the squat exercise itself can put the low back at risk. When descending deeply in the squat position, the inherent biomechanics of the squat motion itself necessitates that the trunk lean forward to maintain the mechanical axis. If, in leaning forward, the weight on the shoulders exceeds the ability of the lifter to maintain the proper back arch, the force across the spine can shift forward and endanger the less resilient structures.

Because of the potential of injury to the low back, the squat exercise is often avoided, despite its effectiveness in developing the important muscles of the lower extremities. The purpose, therefore, of this Invention, is to modify the load application of resistance to the spine and upper body, so that the squat exercise can be performed with minimal risk of injuring the low back.

BRIEF SUMMARY OF THE INVENTION

The concept of the invention is to create from the single downward line of force application of the weight, two separate, opposing points of force application that pivot around a central axis. The source of the resistance is applied through this central pivot and along the mechanical axis of the spine and pelvis, just above the shoulders and behind the neck. The actual pivoting point does not contact the lifter, but instead, transmits the applied load to two opposing lever arms that extend out in opposite directions from this point. The front lever will consist of two parallel, padded rests which will go horizontally forward on either side of the head to reach the front of the shoulders. These lever arms, being positioned forward to the pivot, will tend to rotate upwards and backwards when force is applied to them from the front of the shoulders. The rear lever arm is also attached to the rotating pivot point, and extends posteriorly and vertically downward, towards the low back. When the lifter pushes upward onto the forward lever arms, the rear, lower arm (which is padded) rotates downwardly and forwardly to engage the small of the back. The net effect of the opposing rear and forward arms help protect the lifter in two ways. First, the rear arm applies pressure into the small of the back maintains the protective arched position. Second, the low back now shares the load of the applied force with the shoulders. Thus, the pivoting apparatus prevents flexion of the lumbar spine and distributes the load lower on the trunk.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention are apparent in supplied drawings, FIG. 1 and FIG. 2. The unique features will be readily apparent to those having ordinary skill in the art of exercise and exercise machine construction. The pertinent members or components of the invention are shown first with the apparatus unoccupied in FIG. 1 and then with a user engaged in the apparatus in FIG. 2. The side view with the user in place shows the relationship of the points of contact of the apparatus against the user.

FIG. 1 is a perspective top view of the apparatus showing the spatial relationship of each of the members to each other, and one means for load to be applied to the apparatus.

FIG. 2 is a side view of the apparatus with a user engaged within the apparatus. The side view again demonstrates not only the relationship of each of the members of the apparatus to each other; but also demonstrates the relationship and points of application of each of the components onto the user.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings, wherein the reference numerals throughout both drawings refer to like parts on each drawing. The rotating central pivots, 1, are actually two like members, one on each side. As shown in FIG. 1, each rotating central pivot, 1, consists of first, a cylindrical sleeve attached on one end to a metal bracket, 10, with arms of the bracket extending out in both directions from the attachment point of the sleeve. The rotating central pivot, 1, is also comprised of a metal shaft or axle which is contained within the sleeve. As shown in FIG. 1, the shaft or axle which extends out of each rotating central pivot, 1, extends away from the sleeve and terminates onto and rigidly affixes to the resistance application lever, 4. In this preferred embodiment, the resistance for the performance of the squat exercise is delivered through the resistance application lever, 4, such that a weight or resistance that is applied in a downward direction to the resistance arm lever, 4, will be transmitted from the resistance application lever, 4, and through the shaft member of the rotating central pivot, 1, by means of its rigid attachment to the resistance arm lever, 4.

The resistive force that is applied downwardly to the resistance application lever, 4, is therefore transmitted to the rotating central pivot, 1, by means of the rigid attachment of Its axle component to the resistance application lever, 4. As described previously, the sleeve component of the rotating central pivot, 1, is rigidly attached to a metal bracket, 10, that extends out both forwardly and backwardly from its attachment. By means of Its rigid attachment to the metal bracket, 10, any resistive force encountered by the rotating central pivot, 1, is transmitted into the metal bracket, 10. The rotating central pivots, 1, on each side are coaxial to the other in relation to the respective rotation of the shaft of each within its respective sleeve.

As stated, the metal bracket, 10, extends out in both directions from its attachment to the sleeve of the rotating central pivot, 1. One direction that the bracket extends along is called, “forward”. As seen in FIG. 2, there is an orientation of the user in the apparatus such that the user faces in one preferred direction. The direction that the user faces is called the forward direction. Any lever, armature, or bracket that extends along a path opposite to the forward facing user will be considered to be extending in the “backward” direction. The central point from which the bracket extends in either direction is in fact the rotating central pivot, 1.

The position of the user in relation to the rotating central pivots, 1, is a critical relationship. The user must be positioned in such a way that the axis of the rotating central pivots lies perpendicular and intersects a line that travels along the vertical mechanical axis of the spine of the user. The spinal axis of the user varies somewhat between individuals, but generally lies along a line that begins on the shoulders just behind the head, and then travels down through the spine, the pelvis, and then enters the ground in area of the heels. The relationship of the position of the rotating central pivots to the spine of the user is shown in FIG. 2. The forward portions of each of these metal brackets, 10, also curve slightly downward. These forward portions of metal brackets, 10, have affixed to them a curved, metal-backed, pad or cushion which is called the anterior shoulder pad, 2. The purpose of these pads is to lie against just the front part of the shoulders of the user, i.e. in front of the rotating central pivot, 1, and in front of the user's vertical spinal axis. The lengths of the forward portions of the metal brackets, 10, also cannot extend so far forwardly that the user's spinal axis is no longer aligned with the rotating central pivot, 1. Therefore, the length of the forward portion of the metal bracket, 10, is determined by the position of the rotating central pivot, 1, and how it aligns with the vertical spinal axis and the relationship with the anterior shoulder pads, 2, so that they engage the correct area of the shoulders. The two anterior shoulder pads, 2, are separated by such a distance that permits the user's head to lie between them. The result of this relationship is that as the user exerts an upwardly directed force against the anterior shoulder pads, 2, the front portion of the metal bracket, 10, will tend to rotate upwardly around the axis of the rotating central pivot, 1, simultaneously causing the backward portions of each of the metal brackets to tend to rotate downwardly.

The backward extension of each of the metal brackets, 10, engages at its end a posterior axle, 8, which connects the metal bracket, 10, of one side to the like member of the other. This posterior axle, 8, is connected so that it can freely rotate. This posterior axle, 8, has attached at its midportion a rigid member which extends out and away, lying perpendicular to the axis of the posterior axle, 8. This perpendicular member is called the lumbar pad support post, 3. This support post by virtue of its rigid attachment to the posterior axle, 8, rotates in the same arc of motion as the axle it is attached to.

Along the length of the lumbar pad support post, 3, there is a lumbar pad positioner, 7, which engages and slides along the length of the lumbar pad support post, 3. Once the positioner is in the desired position it can be securely fixed to the post by means of a key or screw that locks the lumbar pad positioner, 7, to the lumbar pad support post, 3.

Once the posterior axle, 8, is rotated into desired position, it will need to then be rigidly locked in that position to prevent the pressure of the users low back from moving it out of the desired position. One means of accomplishing this is demonstrated by item number 6 in FIGS. 1 and 2.

The mechanism indicated by number 6 in these figures is to be called the posterior axle locking mechanism. This mechanism consists of a flange which is rigidly affixed to and extends from the posterior axle, 8, itself. In this embodiment the flange contains a series of holes arranged in a circular pattern at some distance from, and concentric to, the axis of rotation of the posterior axle, 8. Aligned with these holes in the flange of the posterior axle locking mechanism, 6, is a tab extending from and rigidly affixed to a portion of the backward extension of the metal bracket, 10. This tab, likewise, has a hole through it and this hole can align with one of any of the holes contained in the flange of the locking mechanism, 6, depending on the rotational position of the posterior axle, 8. When the lumbar pad support post, 3, is in the desired position, a key shown in item 6 in the figures, can be placed through the hole in the flange of the locking mechanism, 6, and engage the hole in the tab attached adjoining metal bracket, 10. By having a key go through both holes, the locking mechanism, 6, is completely fixed in the desired position.

Attached to the lumbar pad positioner, 7, is the lumbar pad, 5. The lumbar pad, 5, is of such size as to contact and lie wholly within the area called, “the small of the back” or lumbar spine. To help maintain arm position within the apparatus, it is helpful to have handles, 9, available. There are two cylindrical handles that extend out from the front shoulder pads, 2. 

1) An apparatus to maintain spinal alignment during the squat exercise comprising: A rest or plurality of rests that are positioned against the anterior to middle portion of the shoulders generally capable of exerting a downward and posteriorly directed force; A rest or plurality of rests positioned against the lower spine, i.e. small of the back, generally exerting an anteriorly directed force; A connecting member between the anterior shoulder rests and the posterior lower back rests of each side, such that when the user exerts force onto either rest, the opposite rest will exert a reciprocal rotational force against the user; A point on the connecting member between the rests, that lies along the neutral, i.e. mechanical, axis of the spine, where resistance can be applied and transmitted to the user through the anterior and posterior rests; The result of the forces created by the opposing anterior shoulder rests and lower back rests, is that the spine is compelled to remain in alignment and is prevented from flexing forward. 2) An apparatus according to claim 1 wherein the rests applied to anterior and middle potions of the shoulders are comprised of two parallel rests that lie on the left and right side of the shoulders, and contact the front to middle portion of the shoulders; generally capable of exerting a posteriorly directed force. 3) An apparatus according to claim 1, wherein the connecting member between the shoulder rests and the lower back rests is in fact a lever whose pivot point is positioned over the neutral, i.e. mechanical, axis of spine, which generally lies behind the head and over the middle of the posterior shoulders. 4) An apparatus according to claim 1, comprising a connecting member from each of the shoulder rests, which travels through the pivot point of the connecting member and extends posteriorly behind the user and behind the neutral mechanical axis of the spine. 5) An apparatus according to claim 1, wherein the connecting member from the shoulder rests which proceeds posteriorly, past the pivot point, will be intersected by and have attached to it a transverse crosspiece between the connecting members of each side. 6) An apparatus according to claim 1, comprising a lumbar rest attached to the transverse crosspiece between the left and right sides; which can rotate in an arc around this transverse connector for the purpose of engaging the lumbar rest against the low back. 7) An apparatus according to claim 1, wherein the the pivot point on the connecting member between the anterior shoulder rests and the posterior lumbar rests can engage a long lever arm that is hinged on an external, immobile base, such that when the user exerts force on the applied shoulder and lumbar pads, the engaged lever arm will be raised and travel up with the user. Any resistance carried by or applied to the external lever arm will likewise be carried by the user, through the lever arm attachment on the pivot point of the connecting member between the anterior shoulder rests and the posterior shoulder rests. 8) An apparatus according to claim 1, wherein the pivot point on the lever between the anterior shoulder rests and the posterior lumbar rest can have weight resistance applied directly to it by means of a hook, a peg, a post, or a cradle that holds a weight plate, a barbell or a dumbbell onto the pivot. 9) An apparatus according to claim 1, wherein the pivot point on the lever between the anterior shoulder rests and the posterior lumbar rest can have weight resistance applied directly to it by means of a cable or a plurality of cables that exert a downward force. 